This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A106007 #9 Dec 12 2016 02:33:06 %S A106007 0,1,13,14,15,18,19,24,25,26,28,29,35,36,37,39,45,46,48,49,52,55,59, %T A106007 64,65,66,69,73,75,78,79,81,82,85,89,91,95,99,125,126,127,128,129,134, %U A106007 135,136,137,138,143,144,145,146,147,148,149,152,153,154,155,156,157,158 %N A106007 Coster numbers: similar to Friedman numbers (A036057), but here the operations + - * / are allowed. All digits of a number have to be used exactly twice. %C A106007 These numbers were introduced in 2006 in the yearly number puzzle in the Dutch Journal "Pythagoras" (see http://www.pythagoras.nu). It is known that there are infinitely many Coster numbers (result of David Kloet, Albert Hendriks and Arjen Stolk, unpublished). %H A106007 Matthijs Coster, Feb 02 2007, <a href="/A106007/b106007.txt">Table of n, a(n) for n = 0..89</a> %H A106007 Matthijs Coster, <a href="http://www.wiskundemeisjes.nl/20061030/coster-getallen/">www.wiskundemeisjes.nl/20061030/coster-getallen/</a> (in Dutch) %H A106007 Matthijs Coster, <a href="http://www.matcos.nl/sequences/index.html#A106007">www.matcos.nl/sequences</a> %H A106007 Pythagoras, <a href="http://www.pythagoras.nu">www.pythagoras.nu</a> (in Dutch) %e A106007 36 is in the sequence since 3*6+3*6 = 36 %Y A106007 Cf. A036057. %K A106007 base,nonn %O A106007 0,3 %A A106007 _Matthijs Coster_, Dec 31 2006, Feb 02 2007